The value of the insulin-like growth factor binding protein-1 in the cervical–vaginal secretion detected by immunochromatographic dipstick test in the prediction of delivery in women with clinically unconfirmed preterm premature rupture of membranes

Abstract

Objective: The aim of this study was to determine the value of detecting insulin-like growth factor binding protein-1 (IGFBP-1) in the cervical–vaginal secretion in the prediction of delivery in women with clinically uncorfirmed preterm premature rupture of membranes (PPROM). Material and methods: A total of 87 women, gestational age between 20 and 36 weeks were enrolled into this prospective study. Based on the clinical diagnosis, patients were grouped as clinically evident PPROM ( n = 25), clinically suspected PPROM ( n = 42) and women with intact fetal membranes ( n = 20). Detection of IGFBP-1 in the cervical–vaginal secretions was done using a one-step immunochromatographic dipstick test in all women. The outcome measures were gestational age at delivery, neonatal birth weight and duration of the interval between the test and delivery between women with positive and negative test results. Results: The test was positive in all 25 women (100% sensitivity) with clinically evident PPROM and all delivered prematurely, and negative in 19 out of the 20 (95% specificity) women with intact fetal membranes. Among 36 women with clinically suspected PPROM, 13 (36%) tested positive and 23 (63%) tested negative for IGFBP-1. In this group, the mean gestational age and birth weight at the time of delivery were significantly lower in patients with positive test (31.38 ± 2.6 weeks versus 38.61 ± 0.99 weeks and 1761 ± 527 g versus 3500 ± 355 g, P < 0.05 for both). Eleven (85%) of the 13 women with positive test, delivered within 2 weeks after the performance of the test whereas all the women with negative test results delivered after 2 weeks ( P = 0.001). The test had 100, 92, 84 and 100% sensitivity, specificity, positive predictive value and negative predictive value, respectively, for the outcome measure of test–delivery interval. Conclusion: The screening test for IGFBP-1 in the cervical–vaginal secretions is a useful adjunct in the prediction of delivery in women with clinically unconfirmed PPROM.